Method of forming a dual compartment container



` July 2, 1968 P. REPKO 3,390,507

METHOD OF FORMING A DUAL COMPARTMENT CONTAINER Filed Aug. 27. 1964 2 sheetssheet FlG.l

INVENI OR JOHN F? REPKO My, ?ina #W METHOD OF FORMING A DUAL COMPARTMENT CONTAINER Filed Aug. 27, 1964 J. P. REPKO July 2, 1968 2 Sheets-Sheet 2 INVENTOR JOHN F! REPKO United States PatentO 3,390,507 METHOD OF FORMING A-DUAL- COMPARTMENT CONTAINER v John P. Repko, Beaverton, Mich., assignor to The Dow Chemical Company, Midland, Mich., a core poration of Delaware. y r

Filed Aug. 27, 1964, Ser. No. 392,508 3 Claims. (Cl. 53-14) ABSTRACT or THE DISCLOSURE i Dual compartment containers are obtained by `folding a continuous, heat-sealable 'web along its longitudinal center line, while reversibly folding edge' portions of said web to a height not extending beyond the edge of the center fold;-intermittently heat-scaling a transverse strip of said folded web to obtain the desired container width and preferably thereafter triangularly heat-sealing the corners of the reverse folds. a

The present invention relates to a novel container construction and a method for its preparation. More particularly the present invention relates to a dual Compartrnent container made from a single web.

It is one of the objects of the present invention to provide a dual compartment container in which both com partments can be simultaneously filled, sealed, opened, and emptied. It is another object of the present invention to provide amethod for the continuous preparation of such dual compartrnent containers using a rollvof a single heat sealable web.

The objects of the present invention are accomplished by folding a continuous heat sealable web along its longitudinal center line, while reversibly folding edge portions of said web to a height extending up to the edge of the center fold, to for-m four plies with facing heat sealable surfaces between the outer and the inner plies, intermittently heat sealing a transverse strip of said folded web to obtain the desred container width and preferably thereafter triangularly heat scaling the corners of the reverse folds. The resulting dual compartment container formed by two consecutive transverse heat seals is then filled and the edges of the web sealed to the center fold. i i

As will be illustrated in greater detail hereinafter, the open container need not be separated from the continuous Web until after filling and sealing. The two Compart- -ments of the container may be filled consecutively or simultaneously.

Reference is directed to the accompanying drawings for a more detailed description of the preferred embodiments of the present invention inwhich:

FIGURE 1 is a schematic drawing of the folding of the continuous web to form the plies of the dual compartment container of the present invention;

FIGURE 2 is a schematic drawing of the folding of the continuous web to form the plies of the dual compartment container, the heat scaling of the web to form the open dual compartment container, the filling of the container, and the final heat sealing and separation of the filled container, the entire operation being carried out continuously;

FIGURE 3 is a plan view of a dual compartment container containing an easy opening perforation allowing the simultaneous emptying of both compartments;

FIGURE 4 is a plan View of another dual Compartment container of the present invention of modified construction',

FIGURE 5 is a partial sectional view of the container of FIGURE 4 during fa'brication; and

3,390,50`7 Patented July 2, 1968 FIGURE 6 is a schematic sectional view of the dual compartment container of FIGURE 4 after filling and scaling along line 6-6 wherein the container is made from a continuous thermoplastic resin web.

'Referring to FIGURES 1 and 2, a continuous web 10, having an upward .facing heat sealable surface, is fed from roll stock 11 over roll 12 to the folding wheels 13, 14 and- 15. The center folding wheel 14 assisted by. the side folding wheels 13 and 15 folds the web downwardly along its longitudinal center line. The side folding wheels 13 and 15 assisted by guide rolls 16 and 17 fold the edges of the web 18 and 19 upwardly to the edge of the center fold or to any desired lower height of the center fold, thereby forming the four plies of .the dual compartment container. The folded web, in which the heat sealable surfaces of the four plies face each other is then intermittently heat sealed in the transverse direction to form the side seals 20 of the dual compartment containers, such as container 21. Thereafter or simultaneously therewith the folded corners of the compartments are sealed off to form triangular seals 22 giving the come partments the opening spout 23. The transverse seals and the triangular seals may seal just the inner surfaces of the two compartments or rnay seal all four plies together depending on the nature of the web material and the nature of the heating. The sealed corners are then perforated along line 24 to provide an easy openingmethod for the simultaneous opening of both compartments of the container.

The two compartments of the container formed are ei ther consecutively filled as shown in containers 25 and 26, or si-multaneously filled as shown in container 27. The edges of the original web 18 and 19 are then heat sealed to the center fold 28 to form seals 29. The sealed container is parted from the continuous web by bisecting the transverse seals forming the side edges of the container. v

FIGURES 3 and 4 show two forms of dual compartment containers made in accordance with the method of the invention. In FIGURE 3 the edges of the original web are aligned with the center fold 30 and `the corners of the folded upper edges 31 sealed to provide aspout for the contents. Perforation 32 results in the forming of a tear strip 33 to allow easy opening and simultaneous emptying of the contents. In FIGURE 4 a dual comi partrnent container is illustrated in which the outer edges of the original web 34 are brought up to below the edge of the center fold 30. In both FIGURES 3 and 4 the two compartments of each container have sealed edges with the exception of the spout area.

FIGURE 5 shows the container of FIGURE 4 in producton. The web 35 has been folded downwardly forming center fold 36 and the edges of the web 37 and 38 have been brought up to below the center fold to for m the four plies 39, 40, 41 and 42 of the dual compartment container which has been sealed along one of its side edges 43.

FIGURE 6 shows a sectional view of the container illustrated in FIGURE 4 made out of a heat sealable thermoplastic resin web. The four plies of the container 39, 40, 41 and 42 are sealed together to form the top seal 44. It will be apparent that the side seals (such as seal 43 in FIGURE 5) as well as the triangular corner seals (such as seal 31 in FIGURE 4) also result in the scaling of the inner plies when employing a heat sealable thermoplastic resin web. The edges of the original web 37 and 38 are sealed to the center fold 45 below its top edge 46. The spouts of the two compartments are at the edges of the reverse folds 47 and 48. The contents of the two compartments of the container are separated by plies 40 and 41. Tearing of the serration 32 in FIGURE 4 into the spouts 49 allows the simultaneous emptying of the contents. A hole 50 in the extended center fold allows easy storing of the container on a rack.

The continuous web employed is preferably made from a thermoplastic resin such as a polyolefin, polyvnyl halide, polyvinylidene halide, copolymers and interpolymers of a vinylidene halide and a vinyl halide, rubber hydrochloride, a cellulose ester or similar resin. Resin coated paper, cellophane, polyester film, or foil may also be employed in the formation of the dual compartment contaners of the present invention. Of the resins that can be employed, polyolefins, and particularly polyethylenes, are preferred. Where a resin coated .foil or paper is employed as the web, it is necessary that the resin coating be on the side of the plies contacting the contents of the compartments to permit the sealing-in of the container contents. Thermoplastc resin webs or two-way coated paper or foil webs are preferred since they permit the bonding of the two compartments to each other thereby giving greater rigidity and form retention to the container.

The advantages of the illustrated method of forming dual compartment containers will be apparent from the foregoing description of the invention. Thus the containers are formed from readily available continuous web roll. stock by simple mechanical means. The containers are formed continuously and the method is readily employed in combination with an automatic filling station. The containers produced by the present invention allow the opening and emptying of both compartments simultaneously and therefore the instantaneous miXing of the contents on opening which is of significant advantage in many commercial compositions which are formed in situ.

Some of the features illustrated in the drawings and description such as the perforation and the triangular corner seals constitute preferred embodments of the dual compartment containers of the present invention. Alternate means for accomplishing these and other embodiments of the present invention will be clearly apparent to those skilled in the art. Although the invention has been described in terms of heat seals, it is to be realized that similar seals can be obtained by means of appropriate adhesives.

The foregoing description is not intended to limit the invention to the particular embodiments described except as set forth in the appended claims.

I claim:

1. The method of forming a dual compartment container which comprises folding a continuous web having two heat-sealable surfaces along its longitudinal center line, reversibly folding the edges of said web to the center told to a height not extending beyond the edge of the center fold, thereby torming four plies, intermittently heat-sealing a transverse strip of said four plies to each other, triangularly beat-scaling the reversibly folded edges of said web between the transverse seals while leaving a minor portion of said edge unsealed, perforating the triangular seals in a line parallel to the reversibly folded edges, filling the two compartments formed by two consecutive transverse seals of said container, and thereafter scaling the edges of said web to said center told.

2. The method of forming a dual compartment container of claim 1 including the step of parting the container from the continuous web within the sealed transversestrip area after the filling of the container and the scaling of the edges of said web to the center fold.

3. The method of forming a dual compartment container which comprses folding a continuous web having two heat-sealable, thermoplastic resin surfaces along its longitudinal center line, reversibly folding the edges of said web up to the resulting center told to a height not extending beyond the edge of the center fold to thereby form four plies, intermittently beat-scaling a transverse strip of said four plies to each other, triangularly heatsealing the reversibly folded edges of said web between the transverse seals while leaving a minor portion of said edge unsealed, perforating the triangular seals in a line parallel to the reversibly folded edges, filling the two compartments formed by two consecutive transverse seals of said container, and scaling the edges of said web to said center fold.

References Cited UNITED STATES PATENTS 2,929,l 3/ 1961 Abrams et al. 53-29 2,977,729 4/ 1961 Fretchmann et al. 53-29 2,015,972 10/ 1935 Sodergren 229-56 2,416,816 3/1947 Compagnano 229-56 2,362,459 11/ 1944 Barnett 53-28 X 2,565,444 8/ 1951 Waters 53-28 X 2,7l8,105 9/1955 Ferguson et al 53-28 X 3,069,273 12/ 1962 Wayne 53-133 X '3,083,876 4/1963 Schneider et al. 53-133 X 3,224,640 12/ 1965 Schneider et al. 53-14 WILLIAM W. DYER, JR., Pr'mary Examire'.

FRANKLIN T. GARRETT, DAVID M. BOCKENEK,

ROBERT C. RIORDAN, Exam'e's.

N. ABRAMS, Assistant Exam'ner. 

